half mast

halfway down from the top of a mast; hung halfway down the mast (of a flag)

Half-staff or half-mast describes a flag flying approximately halfway up a flagpole or ship's mast (though anywhere from one-third to two-thirds of the way up is acceptable, but see below). This is done in many countries as a symbol of respect, mourning, or distress.The tradition of flying the flag at half-mast began centuries ago to allow the invisible flag of death to fly on top of the mast, thus signifying death's presence, power, and prominence. In some countries, for example the UK, and especially in military contexts, a "half-staff" flag is still flown exactly one flag's width down from its normal position, and no lower, in order to allow for this flag of death. This was the original flag etiquette. However, with larger flags on shorter hoists on many public buildings, the practice of actual half-staff has become common, especially outside the UK, where it is now standard to fly the flag at halfway up the mast regardless of the size of the flag or hoist. (For modern UK practice see below.)
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Noun
1. a position some distance below the top of the mast to which a flag is lowered in mourning or to signal distress
(hypernym) position, place

(n.)
A point some distance below the top of a mast or staff; as, a flag a half-mast (a token of mourning, etc.).
  

half-mast /'hɑ:f'mɑ:st/
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